Particle study apparatus including an axial trajectory sensor

Claim 2

A particle study apparatus including the combination of an axial trajectory sensor and a particle analyzing apparatus; said particle analyzing apparatus having a detecting zone through which the particles are caused to pass for producing pulses, and said detecting zone having an axis; the particles, when passing closest to an axial trajectory through the detecting zone, producing desirable particle pulses having amplitudes which are most nearly proportional to the respective sizes of the particles, and also having a certain approximate shape, and the particles when passing through the detecting zone on trajectories displaced from its axis producing other particle pulses having amplitudes which are not necessarily proportional to their respective sizes and having shapes which tend to depart from said certain approximate shape; said axial trajectory sensor being constructed with an input and an output and arranged to respond to said desirable particle pulses in a first manner and to respond to said other particle pulses in a second manner and further comprising: means for measuring the duration of at least a segment of a particle pulse applied to said input at a plurality of different predetermined fractions of the amplitude thereof and deriving a plurality of duration-measuring pulses having the measured durations of the pulse segments at the respective fractions; means for establishing a standard for a desired duration value for each of at least some of said measured fractional durations; means for comparing each said standard with its related measured fractional duration and for generating a first type of energizing signal if all of the measured fractional durations do not exceed their said standard and a second type of energizing signal if any of the measured fractional durations exceeds its standard; and output means coupled to receive said first and second types of energizing signals for generating, respectively, the first and second manners of response.

Claim 3

A particle study apparatus according to claim 1 in which there is a standard established for all of said measured fractional durations.

Claim 4

A particle study apparatus according to claim 1 in which there is a standard established for all but one of said measured fractional durations.

Claim 5

A particle study apparatus according to claim 1 which includes means providing a pair of fluid bodies, an aperture between the bodies with the bodies being insulated from one another electrically except through said aperture, one of said fluid bodies comprising a suspension of particles, means establishing an electric field in the aperture, means for flowing the sample suspension in the aperture to produce impedance changes in the aperture caused by the passage of particles, said aperture thereby defining said detection zone, means for detecting the impedance changes and producing said desirable and said other pulses, and means for coupling said detecting means to said sensor input.

Claim 6

A particle study apparatus according to claim 1 in which said means for establishing a standard is activated by one of said duration-measuring pulses.

Claim 7

A particle study apparatus according to claim 5 in which said standard establishing means comprises a memory circuit which remembers the minimum duration of previous duration-measuring pulses and produces an output in the form of a quasi-d.c. voltage defining the standard for said one duration-measuring pulse, and said standard establishing means include voltage modifying means, the other standards being defined by modified forms of said quasi-d.c. voltage.

Claim 8

A particle study apparatus comprising the combination of a Coulter type of particle analyzIng device and an axial trajectory sensor, said sensor comprising: means for measuring the duration of each particle pulse produced by said analyzing device at a plurality of different predetermined fractional amplitudes, means for comparing at least some of such duration measurements with a standard established for the duration of each fractional amplitude and means for rejecting those particle pulses, whose compared measurements at all of the fractional amplitudes do not meet such standards.

Claim 9

A particle study apparatus comprising the combination of a Coulter type of particle analyzIng device and an axial trajectory sensor, said sensor comprising: means for measuring the duration of each particle pulse produced by said analyzing device at a plurality of different predetermined fractional amplitudes, means for comparing at least some of such duration measurements with a standard established for the duration of each fractional amplitude and means for rejecting those particle pulses, whose compared measurements at all of the fractional amplitudes do not meet such standards.

Claim 10

A particle study apparatus according to claim 7 in which means are provided for establishing said standards on the basis of the measurement of the duration of at least one fractional amplitude of said each particle pulse.

Claim 11

A particle study apparatus according to claim 8 in which a standard is established for all fractional amplitudes including said one fractional amplitude.

Claim 12

A particle study apparatus according to claim 8 in which a standard is established for all fractional amplitudes but said one fractional amplitude.

Claim 13

A particle study apparatus according to claim 8 in which said standard establishing means includes means for comparing the measurement of the duration of said one fractional amplitude with the duration of previous particle pulses made at said one fractional amplitude.

Claim 14

A particle study apparatus according to claim 8 in which said Coulter type of particle analyzing apparatus includes means providing a pair of fluid bodies, an aperture between the bodies, the bodies being insulated from one another electrically except through said aperture, one of said fluid bodies comprising a suspension of particlEs, means for establishing an electric field in the aperture, means for flowing the sample suspension in the aperture to produce impedance changes in the aperture caused by the passage of particles, means for detecting the impedance changes and producing said desirable and undesirable pulses, and means for coupling said detecting means to an input to said axial trajectory sensor.

Claim 15

A particle study apparatus comprising the combination of an axial trajectory sensor and a Coulter type of particle analyzing apparatus said Coulter type of particle analyzing apparatus including means providing a pair of fluid bodies, an aperture between the bodies and the bodies being insulated one from the other except through said aperture, one of the fluid bodies comprising a sample suspension of particles, means establishing an electric field in said aperture, means for flowing the sample suspension in the aperture to produce impedance changes in the aperture caused by the passage of particles, means for detecting the impedance changes and producing desirable and undesirable particle pulses, and means for coupling said detecting means to an input terminal means of said axial trajectory sensor; particles passing through said aperture generating desirable particle pulses whose amplitudes are most nearly proportional to their respective sizes when passing closest to an axial trajectory through said aperture and having thereby a certain approximate shape and in which particles passing through said aperture on trajectories displaced from the axis generating undesirable particle pulses whose amplitudes are not necessarily proportional to their respective sizes and whose shapes tend to depart from said certain approximate shape; said sensor acting to respond to desirable pulses and not to respond to said undesirable particle pulses and comprising: input terminal means and output terminal means having a channel for passage of electrical signals between the terminal means with switch means in said channel to control the signals which appear at the output terminal means, the input terminal means adapted to have the desirable and undesirable particle pulses applied thereto, means for measuring the duration of at least a segment of a particle pulse applied to said input terminal means at a plurality of different predetermined fractions of the amplitude thereof and deriving a plurality of duration-measuring pulses having the measured durations of the pulse segments at the respective fractions, means for converting each said duration-measuring pulse into a respective electrical time signal pulse whose amplitude is proportional to the duration of the duration-measuring pulse from which it has been converted whereby to derive a plurality of electrical time signal pulses, means connected with said converting means acting to establish for at least less than all of said electrical time signal pulses individual to said respective fractions a voltage level for each said electrical time signal pulse, each electrical time signal pulse derived from a desirable particle pulse falling below its so-established voltage level and if derived from an undesirable particle pulse falling above its so-established level, means comparing the amplitude of each of said electrical time signal pulse individual to said respective fraction with its so-established voltage level and producing one type of energized signal if said last-mentioned electrical time signal pulse is less than its so-established voltage level and producing a second type of energizing signal if said last-mentioned electrical time signal pulse is greater than its so-established voltage level, means for producing a strobing pulse of predetermined duration for each particle pulse applied to said input terminal means, and gating means having said strobing pulse applied thereto, every energizing pulse produced by said comparing means also being applied to said gating means, said gating means being connected to said switch means in the channel and acting to opErate said switch means to pass a signal derived from said input terminal means when said strobing pulse is applied, but only if every energizing signal is of the first type.

Claim 16

A particle study apparatus comprising the combination of an axial trajectory sensor and a Coulter type of particle analyzing apparatus said Coulter type of particle analyzing apparatus including means providing a pair of fluid bodies, an aperture between the bodies and the bodies being insulated one from the other except through said aperture, one of the fluid bodies comprising a sample suspension of particles, means establishing an electric field in said aperture, means for flowing the sample suspension in the aperture to produce impedance changes in the aperture caused by the passage of particles, means for detecting the impedance changes and producing desirable and undesirable particle pulses, and means for coupling said detecting means to an input terminal means of said axial trajectory sensor; particles passing through said aperture generating desirable particle pulses whose amplitudes are most nearly proportional to their respective sizes when passing closest to an axial trajectory through said aperture and having thereby a certain approximate shape and in which particles passing through said aperture on trajectories displaced from the axis generating undesirable particle pulses whose amplitudes are not necessarily proportional to their respective sizes and whose shapes tend to depart from said certain approximate shape; said sensor acting to respond to desirable pulses and not to respond to said undesirable particle pulses and comprising: input terminal means and output terminal means having a channel for passage of electrical signals between the terminal means with switch means in said channel to control the signals which appear at the output terminal means, the input terminal means adapted to have the desirable and undesirable particle pulses applied thereto, means for measuring the duration of at least a segment of a particle pulse applied to said input terminal means at a plurality of different predetermined fractions of the amplitude thereof and deriving a plurality of duration-measuring pulses having the measured durations of the pulse segments at the respective fractions, means for converting each said duration-measuring pulse into a respective electrical time signal pulse whose amplitude is proportional to the duration of the duration-measuring pulse from which it has been converted whereby to derive a plurality of electrical time signal pulses, means connected with said converting means acting to establish for at least less than all of said electrical time signal pulses individual to said respective fractions a voltage level for each said electrical time signal pulse, each electrical time signal pulse derived from a desirable particle pulse falling below its so-established voltage level and if derived from an undesirable particle pulse falling above its so-established level, means comparing the amplitude of each of said electrical time signal pulse individual to said respective fraction with its so-established voltage level and producing one type of energized signal if said last-mentioned electrical time signal pulse is less than its so-established voltage level and producing a second type of energizing signal if said last-mentioned electrical time signal pulse is greater than its so-established voltage level, means for producing a strobing pulse of predetermined duration for each particle pulse applied to said input terminal means, and gating means having said strobing pulse applied thereto, every energizing pulse produced by said comparing means also being applied to said gating means, said gating means being connected to said switch means in the channel and acting to opErate said switch means to pass a signal derived from said input terminal means when said strobing pulse is applied, but only if every energizing signal is of the first type.